A new type of capacitor has been developed for use in electric and electronic circuits. The capacitor comprises an intimate mixture of electrically conductive particles and non-conductive particles spaced between two conductive plates kept nearly equally separated. The random nature of the mixture promotes the formation of a network of conductive particles that provide an extended surface area.
All capacitors, sometimes known as condensers, are based on the principle that an electric charge on one conductor will induce a charge of opposite polarity on another conductor which is separated from the first by insulating material. In practice, the conductors usually consist of two parallel plates that may be flat or spirally wound. These plates are separated from each other by a thin layer of insulating material known as a dielectric. Such an arrangement has the ability to store electric charge and electric energy. The properties of these devices also render them extremely useful in every conceivable electronic application.
The ability of a capacitor to store an electric charge depends on several characteristics. The capacitance is defined as the ratio of the charge on one conductor divided by the applied voltage. This capacitance has been determined to be proportional to the area of the plates and inversely proportional to the distance between the plates. The proportionality constant is known as the dielectric constant, which depends on the properties of the insulating material.
In attempts to increase capacitance, the electrolytic capacitor was developed. In this device a plate, often made of tantalum, is coated with an oxide layer that acts as a dielectric. The coated plate is immersed in a solution which functions as the complementary plate. Various modifications of the electrolytic capacitor have succeeded in increasing its performance significantly. This type of capacitor, however, is limited to use with direct current.
Efforts continue to enhance the performance of capacitors. Newer applications, such as electronics used in space exploration, require devices of minimum size, capable of operating at higher temperatures. Therefore, it is an object of the present invention to provide for an improved capacitor design, one that offers the maximum capacitance in the smallest possible size. This and other objects, features and advantages of the invention will be apparent from the accompany drawing and the following description.